Artificial sole-stock or composition material.



. Without tearin which will oermit its bein a i z:

Crude rubber -G1O111'. d cured scrap rubber of puie gum nature 23. 00 High grade auto tire shoddy 17.5 Ground cured tire carcass h 36. 00 7'0 Sulfur 1. 125% Gas black 125% Lime -00 v as ems BEAN BELDEN', 0F AKRQN, OHIO, ASSIGNOR TO THE MELLER RUBBER EOMPANY, 0F AKRON, OHIG, A CORFQE-ATION 015' 01-110.

EQ'EIEL'CIAL SQLE STQCK GB CQMEQSITIGN MATERIAL.

No Brewing.

-material designed to be used for the soles of boots and shoes.

The object of the invention is to provide a material having a high abrasion test so that it Will be e 'ceedingly durable in use and in fact be equal to or exceed leather in its Wear resisting qualities; which will be of a fibrous nature so as to be capable of holding stitches readil cut to the rooer shaue and which Will he of a consistency of character Which will enable the edge of the sole to be buffed in a manner similar to the ordinary leather sole.

With these objects in view the invention comprises the novel composition and method of making the same hereinafter described and particularly defined by the appended claims.

A specific composition which Ihave found to possess the characteristics above recited, consists of the following:

oring material would be substituted accord.

ing to circumstances of the case' it will also be ObYl'OUS that some other suitable allzuli might be substituted for the Specification of Letters Eaten? Patqgnted D943, 189E191 "3,

Application filed June s, 1916. Serial are. 102,532.

lime Without departing from the spirit of my invention.

In manufacturing my improved stock or leather substitute I grind up cured scrap rubber of a pure gum nature, such for example as scrap or Worn out innertubes. 1 then take cured scrap automobile tire caslugs and remove the beads and threa leav ing only the friction-or cotton fabric coated with rubber, these having a very high grade long staple cotton constituent together tvith a portion of high grade vulcanized rubber,

such as is used in the manufacture of high grade tires, such remaining parts of the tires being placed on the grinding mill, whereby they are reduced to the proper degree of fineness.

This material has been selected due to the fact otthis particular combination of high grade rubber with low specific gravity with a proportion of high grade long staple cotton fiber found in high grade tires, resulting in exceedingly low cost with hi h grade cotton base and this particular combination of cotton and rubber produces a material of lov specific gra 'ity which gives to the finished sole the desired quality of density and flexibility Without stretch.

The composition above described is then rolls, the ratio of speed of .Which enters very materially into the final result. Ordinary mixing mills used'in rubber factories having a decided dillerencc in speed between the back and front rolls, or in other Words, the friction between the two rolls quitedecidedly pronounced, used ordinarily in grinding in mineral pigments, etc., will not do. It was discovered that this was very detrimental in mixing this combination of materials orcompound and it "was found necessary to construct a special mill with a. much smaller differential. The using of a very slight ditferential between these two rolls was a dominating feature in producing the final results. The mixture is then reduced to slab form of the required thickness on a calender, cut out into suitable shapes, if desired, and vulcanizing under pressure in a mold in a press, in the ordinary or any desired manner. Whatl claim is 1. The hereindescribed plastic composition comprising crude rubber, comminuted vulcanized rubber scrap, ground or eomminuted vulcanized scrap friction fabric, sulfur and an alkali, in substantially the proportions specified. I

2. The hereindescribed plastic composition comprising crude rubber, ground cured scrap rubber of a pure gum nature, auto tire shoddy, ground cured tire carcass, sulfur and lime in substantially the propor- 10 tions specified.

3. The hereindescribed method of making s q a plastic composition which consists 1n m1X mg together crude rubber, commmuted scrap vulcanized rubber, comminuted ground frietion fabric, sulfur and an alkali, in a roller 15 mill, one of the rolls of which has a speed slightly in excess of the other. y

In testimony whereof, I afiix my signature.

RUSSELL DEAN BELDEN. Witnesses:

C. A. WOLF, (11E. ROBERTS. 

